Across
1
Repeated addition
3
The number representing nothing
4
Distance from center to edge of circle
7
Number less than zero
9
Rectangle with four equal sides
11
Number with digits after a point
12
System of ordered marks for measuring
Down
2
Number that divides evenly into another
5
Reference line in a graph
6
Amount of space an object occupies
8
Math using letters for unknown values
10
Line touching circle at one point